Transmission



y 1951 J. 5. ALSPAUGH 2,559,922

TRANSMISSION Filed Jan. 3, 1947 INVENTOR.

James S. A/spaug/z Patenteii July 10, 1951 rnsusmssrou James S.Alspaugh, Portsmouth, Ohio Application January 3, 1947, Serial No.720,052

4 Claims. (Cl. 74-732) Torque responsive transmiss on This inventionrelates to a torque responsive transmission, and more particularly to amechanical device for transmitting power from a driving shaft to adriven shaft in such manner that the speed ratio of the driven shaftrelative to the driving shaft is dependent on the torque applied to thedriving shaft with reference to the load to which the driven shaft issubjected.

An object of the invention is to provide an infinitely variablemechanical transmission having driving and driven shafts interconnectedby mechanical gearing which is controlled in such manner that the ratioof speed may vary in proportion to variations in the torque and load towhich the driving and driven shafts are sublected.

A further object of the invention is to provide a mechanicaltransmission including a fluid clutch and including aligned driving anddriven shafts interconnected by planetary gearing which is rotatablymounted in a frame carried by the driven member'of the fluid clutch, theframe being controlled by said clutch in such manner that it may moverelative to a stationary member to vary the torque and speed ratios ofthe driving and driven shafts.

Still another object of the invention resides in the provision of atransmission having gear-connected shafts wherein means are provided forcontrolling the speed of rotation of the gear carriers and gears to varythe torque transmitting characteristics of the transmission.

A further object of the invention is to provide a gear of the typeindicated wherein the operator may, when on downgrade, utilize thebraking effect of the vehicle engine to decelerate the vehicle.

Further objects and advantages of the invention will be apparent fromthe following description, taken in connection with the appendeddrawing, wherein:

Fig. 1 is a longitudinal sectional view of a transmission embodying theinvention; and

Fig. 2 is a diagrammatic view in section of the apparatus forcontrolling the brake shown in Fi 1.

It is to be understood that the invention is not limited in itsapplication to the details of construction and arrangement of partsillustrated in the accompanying drawing, since the invention is capableof other embodiments and of being practiced or carried out in variousways. Also it is to be understood that the phraseology or terminologemployed herein is for the purpose of description and not of limitation.

In the device illustrated in Fig. 1, the power or driving shaft H) isadapted to be connected to any suitable source of power, such as theengine of an automotive vehicle. Aligned with the power shaft i0 is afinal driven shaft l2, which may be connected through a differential,not shown, to the driving wheels of the vehicle. The forward end of theshaft I2 is formed with an enlarged splined section H, a planecylindrical section is, and an axial extension is which is rotatable inan axial bore formed in the power shaft l0. Rotatably mounted on theextension II is a sleeve 20 which is secured by means of clutch teeth 22to the shaft It, the latter being formed with corresponding dental teethwhich with teeth 22 form a permanent connection between the two members.At the other end of sleeve 20 is formed a driving sun gear 24 for apurpose hereinafter explained. Rotatable on the sleeve 20 is a secondsleeve 26, formed at its forward end with a flange 28 which matches asimilar flange 30 formed on the power shaft ll. The rear end of thesleeve 26 is formed with a radial flange 32 and a cylindrical portion24. A disc 36 is secured to the portion 34 and serves to form therewitha casing for the planetary gears hereinafter described.

Secured to the flange 30 and 28 respectively are the impeller element 40and the turbine element 42 of a fluid clutch of known type, which actsin the known manner to exert a torque upon the sleeve 26 proportionateto the speed of the engine and to the load upon the turbine element.Secured to the flange 30 is a housing for the fluid clutch, made up of aplate 44 and an element 46 which has an oil seal 48 rotatably engagingthe sleeve 26. In addition, the entire mechanism may be enclosed withina gear case 50 which is formed at 52 with a journal for the driven shaftI2. A pan 54 is secured to the under side of the case 50. A flywheel 55may be secured to the periphery of plate 44, to be engaged by the enginestarter in the usual manner.

An idler gear 56 is rotatably mounted on the central section 16 of shaft12. Immediately posterior to the gear 56 is an intermediate shaft in theform of a sleeve 58 which is formed at its forward end with a gear 60and at its rear end with a gear 62. The intermediate shaft or sleeve 58is freely rotatable on the cylindrical section ii of the driven shaftI2.

Fixed to the sleeve 58 is a brake drum 64. designed to be engaged by abrake band it to pre- 3 vent creeping of the vehicle at idling speeds ofthe engine.

A pinion shaft I has its ends mounted in flange 32 and disc 36, andcarries a sleeve having formed thereon a larger planetary gear I2 whichmeshes with the driving sun gear 24, and a second smaller planetary gearI4 which meshes with the idler gear 56. A second pinion shaft I6 has itsends mounted in members 32 and 36 opposite the shaft I0 and similarlycarries a sleeve upon which are formed a smaller planetary gear I8,which meshes with the idler gear 56, and a larger planetary gear 80which meshes with the gear 60 on sleeve 58.

A countershaft 82 is journaled in suitable bosses or extensions of thecase 50, and carries a sleeve which has formed thereon a larger gear 84which meshes with gear 62, and a smaller gear 86 which meshes with anidler gear 81. For purpose of producing a reverse drive, the gear 88 isformed upon a sleeve 90 which is splined upon the splined section I4 ofthe driven shaft I2. A gear shift lever 92 engages the sleeve 90 and isdesigned to bring the gears 88 and 81 into engagement for this purpose.

The sleeve 90 is formed at its forward end with clutch teeth 94 which,upon movement of the sleeve forwardly, engage corresponding teeth 80formed on the rear end of sleeve 58, to couple the sleeve to the drivenshaft I2 for the purpose of forming a positive connection between thesleeve 58 and the driven shaft I2.

The apparatus for controlling the brake 64, 66 is illustratedschematically in Fig. 2, which shows the parts in the positions whichthey occupy when the brake is applied. The apparatus comprises a fluidpump I00 which is driven through a rod II from a moving part of theengine, and is designed to draw oil or other hydraulic fluid from areservoir I02 and pump it under pressure through a conduit I04 to acylinder I06, the piston I08 of which is connected by means of a rodIIIl to the movable end of brake band 66. The fixed end of brake band 66is connected to a stationary element III of the gear case 50. Anysuitable means such as a spring II2 may be employed to urge the brakeband 06 to released position. In order to maintain the pressure of fluidin the line at a fairly constant value, a pressure relief valve H4 isinserted in the conduit I04, and operates when high pressures occur tobypass a portion of the fluid through a, port H5 and back to thereservoir I02. In order to vary the pressure of fluid in accordance withengine speed, a second valve H6 is placed in the line in series withvalve H4 and is moved by means of a lever H8 and a governor I20 towardits lower position as the speed of the engine increases, so as to bypassthe fluid through a. port I2I back to the reservoir I02 and therebyrelease the brake partially or completely at engine speeds above idlingspeed. The governor may be of any suitable type, and is connected bygearing I22 to a moving part of the engine, such as the cam shaft. Inorder to permit the operator to vary the fluid pressure manually andthereby release the brake, as for towing, a manual valve I24 is alsoplaced in the conduit I04 and is operative to bypass fluid through aport I25.

The operation of the apparatus is as follows:

Assume that the vehicle is stationary, the driven shaft I2 also beingstationary, and that the motor of the vehicle is operating at idlingspeed, rotating the shaft I0 and the impeller 40, while clutch teeth 94,88 are in neutral (disengaged) position as shown in Fig. 1, under thesecircumstances the brake 64, 86 will be applied by the governor I20 sothat the sleeve 58 will be held in stationary position. The shaft I0 isrotating in one direction and the sleeve 26. impelled by the reaction ofthe planetary gears, is rotating in the opposite direction, so that thegear 88 is rolling around the periphery of gear 60, the latter gearacting as a stationary track. In order to propel the vehicle by motivepower applied through the present transmission, the operator willactuate lever 82 to cause the clutch teeth 84, 88 to engage. The turbineelement 42 will then be connected through the sleeve 26 and the otherelements above described-to the driven shaft I2, but since little torqueis applied through the fluid clutch at idling speeds the reaction of theplanetary gears will cause the sleeve 26 to operate in a reversedirection as above noted; that is, if the driving shaft I0 is rotatingin the clockwise direction, as viewed from the left in Fig. l, theshafts l0 and I6 will rotate about shaft I2 in the counterclockwisedirection. Thus the driven shaft I2, although lightly urged towardrotation in the clockwise direction, will be held stationary by thebrake 64, 66. It will be seen that at this stage the turbine 42 isrotated by the sleeve in a direction opposite to that in which it isurged by the force of the fluid in the fluid clutch.

If now engine speed is increased, the brake 84, 66 will be released bythe governor I20 or manual valve I 24, and the torque exerted upon theturbine 42 will increase. This will tend to retard the reverse rotationof the turbine 42 and the gear carrier 32, and will correspondinglyincrease the torque exerted through the gear carrier 32, the sleeve 58,and the clutch teeth 94, 96 to the driven shaft I2 to the point wherethe driven shaft'will exert suflicient torque upon the drivin wheels'tomove the vehicle. The transmission is then operating at a high reductionratio, being in effect in low gear. As the vehicle speed increases, orthe torque required to turn the driven shaft I2 decreases, the fluidclutch will further retard the reverse rotation of the gear carrier 32,which will further decrease the reduction ratio through thetransmission. When the speed and torque are at such value that the gearcarrier 32 remains stationary, the efiective reduction is through thegears 24, I2, I4, 56, I8, and 60, givin an intermediate speed.

Further reduction of the torque required to turn the driven shaft, orfurther increase in the motor speed, will cause the turbine 42 of thefluid clutch to begin to rotate in the same direction as the impeller40. If the elements 40, 42 of the fluid clutch were to rotate at thesame speed, the planetary gears would not turn on their axes, but wouldsimply move about the shaft I2 in a planetary manner in the clockwisedirection, and the transmission would then be in direct drive. However,the fluid clutch will at all times permit a slight slippage, and thiswill cause a slight reduction of gear ratio in the transmission such asis characteristic of a transmission which includes a fluid clutch.

In order to produce a reverse drive, the operator will move the sleeve90 rearwardly, thus disengaging the clutch teeth 94, 96, and moving theparts to the point where the gear 88 engages the gear 81, which willproduce rotation of the driven shaft I2 in a direction opposite to thatabove described. This is in effect simply the conventional reversegearing. It will be noted, however, that the transmission is torqueresponsive even when in reverse.

It will be seen that the transmission maybe used not only in automobilevehicles but in power hoists and wherever an infinitely variable transmission is desired.

For purposes of considering the action of the transmission, the geartrain comprising gears 24 and 12 may be referred to as train one, thetrain comprising gears 14, 56, and 18 as train two, and the traincomprising gears 80 and'60 as train three. Using this terminology,rotation of drive shaft l and pinion gear 24 of train one is transmittedto planet gears 12 and 14. These gears are carried by gear carrier 32and are connected to the idler sun gear 56 of train two. Therebyrotation of planet gears 12 and 14 against the idler sun gear 56 andagainst train two will rotate backwardly the gear carrier 32, whichcarries the pinion ears 18 and 80. Thus backward rotation of planet gear14 rotates planet gear- 12 backwardly around-the driving sun gear 24 asthe latter rotates planet gears 12 and 14. Gear carrier 32 wil rotateplanet gear 18 around sun gear 56 of train two. This rotation of planetgear 18 by the gear carirer 32 is transmitted to planet gear 80, whichis meshed with gear 60 of train three secured to driven shaft 12. a i

Although the invention has been described with particular reference tothe illustrated embodiment thereof, it may be embodied in other formswithin the skill of artisans inthis art, and is 6 driving shaft and aturbine fixed to carrier, a source of fiuid pressure, a brake for theintermediate shalt, fluid pressure actuated means operable atyslowspeeds of the driving shaft to actuate said brake to lock theintermediate shaft against rotation, and speed responsive means operatedby an increase of speed of the driving shaft to release said brake.

3. In a transmission, a driving shaft. an intermediate shaft, a finaldriven shaft, a sun gear fixed to the driving shaft, a sun gear oflarger diameter fixed to the intermediate shaft, an idler sun gear ofstill larger diameter rotatably mounted between the sun gears fixed tothe driving and intermediate shafts, a planet carrier having one set ofpinion gears of large and smaller diameters meshing with the sun gearfixed to the driving shaft and with the idler sun gear respectively, andhaving another set of pinion gears of small and larger diameters meshingwith the idler sun gear and with the sun gear fixed to the intermediateshaft respectively, and-a fluid coupling having an impeller fixed tothe'driving shaft and a turbine fixed to the planet carrier to controlthe speed ratio by retarding reverse rotation of the carrier producedbysaid different sized sun gears as the speed of the impeller increases.

not limited except by the terms of the following claims. 5

I claim: I v 1. In a transmission having a driving shaft,

an intermediate shaft, a final driven shaft, sun

gears fixed to the driving and intermediate shafts, a fluid couplinghaving an impeller fixed to the driving shaft, a turbine associated withthe impeller and adapted to be driven thereby, a planetary gear trainhaving a carrier operably connected to the turbine, an idler gear,pinion gears mounted in the carrier and interconnecting the sun gearfixed to the driving shaft and said idler gear, additional pinion gearsmounted in the carrier and interconnecting the idler gear and the sungear fixed to the intermediate shaft, a source of fluid pressure, abrake for the intermediate shaft, fiuid pressure actuated means operableat slow speeds of the driving shaft to actuate said brake to lock theintermediate shaft against rotation, and. speed responsive meansoperated by an increase of speed of the driving shaft to release saidbrake.

2. In a transmission, a driving shaft, an intermediate shaft, a finaldriven shaft, a sun gear fixed to the driving shaft, a sun gear oflarger diameter fixed to the intermediate shaft, an

idler sun gear ofstill larger diameter rotatablyv mounted between thesun gears fixed to' the driving and driven shafts, a planet carrierhaving a set of pinion'gears of large and smaller diameters meshing withthe sun gear fixed to the driving shaft and with the idler sun gearrespectively and having another set of pinion gears of small and largerdiameters meshing with the idler sun gear and with the sun gear fixed tothe intermediate shaft respectively, a fluid coupling having an impellerfixed to the by an increase of speed file of this patent:

4. In combination with driving and intermediate shafts of a transmissionfor a motor vehicle having sun gears fixed to the driving andintermediateshaftsa fiuid coupling havingan impeller fixed to thedriving shaft, a turbine associated with the impeller and adapted to bedriven thereby, a planetary gear train having a carrier operablyconnected to the turbine, an idler gear, pinion gears mounted in thecarrier and interconnecting the sun gear fixed to the driving shaft andsaid idler gear, additional pinion gears. mounted in the carrier andinterconnecting the idler gear and the sun' gear to the intermediateshaft, a source of fiuidpressure, a brake for the intermediate shaft,means operable by said fluid pressure at slow speeds of the drivingshaft to actuate said brake to.

lock the intermediate shaft against rotation to prevent movement of thevehicle under idling conditions, and speed responsive means operated ofthe driving shaft to release said brake, JAMES s. ALSPAUGH.

REFERENCES CITED The following references are of record in the UNITEDSTATES PATENTS Great Britain Feb. 11, 1936 the planet

